The past decade has brought a wave of effective CLL treatments—including pirtobrutinib, acalabrutinib, zanubrutinib, venetoclax, and the investigational sonrotoclax—but this abundance of options has made treatment selection increasingly complex. According to Dr. Mary Ann Anderson of Royal Melbourne Hospital, the lack of head-to-head trial data means clinicians can't simply default to the newest agent; instead, they must carefully tailor decisions to each patient's profile.

A central decision point is choosing between continuous BTK inhibitor therapy and time-limited BCL-2 inhibitor-based regimens. BTK inhibitors are easy to initiate but carry risks of hypertension, atrial fibrillation, and bleeding, and resistance mutations can develop over time—limiting future sequencing options. BCL-2 inhibitor regimens require more intensive monitoring (due to tumor lysis syndrome risk) but may preserve more downstream treatment flexibility, as relapses off therapy are less likely to carry resistance mutations.

Key Takeaways:

• Pirtobrutinib can rescue covalent BTK inhibitor failures, but the reverse has not been demonstrated—sequencing order matters
• Time-limited BCL-2 inhibitor therapy may allow retreatment at relapse, complicating traditional PFS comparisons
• Patient comorbidities, concurrent medications, and personal preferences (e.g., pill burden, treatment duration) should all factor into frontline CLL decisions

Why it matters: With CLL treatment horizons spanning 10–20 years, the frontline choice isn't just about initial response—it shapes every subsequent line of therapy. Getting individualization right from the start could meaningfully improve long-term outcomes.